Experimental study on fire resistance performance of bolted glued laminated bamboo spliced connections subjected to axial loading
In this paper,nine axially loaded bolted glued laminated bamboo connection specimens were designed and tested at normal temperature and in fire to investigate the fire endurance of spliced connections subjected to axial loading.The test parameters included connection type,bolt end distance and load ratio.The fire endurance was determined based on the test results.The results indicate that the bolt end distance has an important influence on the failure modes of the specimens tested at normal temperature.Splitting failure perpendicular to the bamboo grain direction and longitudinal shear failure occurr in the glued laminated bamboo components when the specimens in fire are close to ultimate failure.A higher load ratio can lead to more notably bending deformation in the bolts of the specimens in fire.The load ratio plays an important role in the fire endurance of the connections.When the load ratio increases from 0.3 to 0.5,the fire endurance of the connections with slotted-in steel plates and a bolt end distance of 7 and 10 times the bolt diameter,and the connections encased with steel plates with a bolt end distance of 7 times the bolt diameter,decreases by 27.6％,32.9％and 37.2％,respectively.The bolt end distance has a significant impact on the fire endurance of the slotted-in steel plate connections.When the bolt end distance increases from 7d(d is the bolt diameter)to 10d,the connection fire endurance with load ratios of 0.3 and 0.5 increases by 25.1％and 15.9％,respectively.The fire endurance of the bolted glued laminated bamboo connections subjected to axial loading meets the requirements of current timber structure design standards for similar types of bolted connections.The charring rate of the glued laminated bamboo decreases with the extension of fire exposure time.The average charring rate of the glued laminated bamboo is close to the nominal linear charring rate(0.90 mm/min)prescribed by T/CECS 1101-2022'Standard for design of engineered bamboo structures'.
万方数据
维普
